P0378 - A Pain in the Buttocks: An Unusual Presentation of Esophageal Adenocarcinoma

Minh N. Tran, MD¹, William M. Tung, MD¹, Kevin Kline, MD², Jaison S. John, MD¹, Kevin Brown, MD¹, Fatima Iqbal, MBBS¹, Mohammad Abdallah, MD¹, Kashif Khan, MD^1
1University of Texas Medical Branch at Galveston, Galveston, TX; ²University of Texas Medical Branch, Galveston, TX

Introduction: Esophageal cancer with soft tissue and intramuscular metastases is rare with only a few cases reported in the literature. Here, we report a case of esophageal adenocarcinoma diagnosed on biopsy of a soft tissue metastasis. This case demonstrates the aggressive nature of this malignancy and the high index of suspicion needed for unusual soft tissue symptoms.

Case Description/Methods: A 54-year-old man with past medical history of untreated hepatitis C and chronic back pain presented after a syncopal event and one episode of hematemesis. The patient additionally had complaint of back and gluteal pain. The physical exam was notable for tenderness in his upper back and left posterior thigh. Labs revealed hemoglobin 6.9 g/dL, hematocrit 22%, mean corpuscular volume of 84.3 fL, ferritin level of 9.2 ng/mL. Upper endoscopy revealed localized friability, necrosis, and ulceration in the lower third of the esophagus. Biopsy of the esophagus was not taken due to contact bleeding from severe mucosal friability and recent hematemesis. Computed tomography (CT) with contrast of the abdomen and pelvis showed mural thickening of the distal esophagus and gastroesophageal junction and a large peripherally enhancing centrally necrotic mass in the left proximal adductor muscles of the thigh. CT thorax revealed a pathologic fracture along the right eight rib with soft tissue involvement. Interventional radiologists performed a core needle biopsy of the thigh mass. The biopsy revealed metastatic adenocarcinoma with CK7 (+), CK20 (+), CDX2 (+), and TTF-1 (-) on immunohistochemistry (IHC). The diagnosis was favored to be esophageal adenocarcinoma with metastasis to bone and soft tissues.

Discussion: Soft tissue metastases from primary solid tumors are uncommon and constitute less than 3% of all soft-tissue malignancies. Esophageal cancer is an aggressive disease with poor prognosis once metastasized and may have no specific symptoms even at advanced stages. About 1.9% of patients with primary esophageal cancer (more commonly adenocarcinoma) have metastasis to soft tissues, with the most common site of soft tissue metastasis being skeletal muscle. In the absence of primary tissue histology, clinical history, endoscopic exam, and radiographic findings are essential in the diagnostic process. In addition, IHC studies of the metastatic tissue can provide important clues to locate its primary site. CDX2 and TTF-1 can help differentiate intestinal tract cancer from malignancy of the lungs and other locations.


Figure: Endoscopic view of circumferential luminal narrowing in the lower third of the esophagus with severe mucosal changes characterized by localized friability, necrosis, and ulceration (A-C). CT abdomen and pelvis showing a 5.4 cm x 4.9 cm peripherally enhanced centrally necrotic mass in the left proximal adductor muscles of the thigh (D). The needle core biopsy of the left thigh showing metastatic adenocarcinoma with positive CDX2 immunostain (E) and negative TTF-1 immunostain (F).


Disclosures:
Minh Tran indicated no relevant financial relationships.
William Tung indicated no relevant financial relationships.
Kevin Kline indicated no relevant financial relationships.
Jaison John indicated no relevant financial relationships.
Kevin Brown indicated no relevant financial relationships.
Fatima Iqbal indicated no relevant financial relationships.
Mohammad Abdallah indicated no relevant financial relationships.
Kashif Khan indicated no relevant financial relationships.


Minh N. Tran, MD¹, William M. Tung, MD¹, Kevin Kline, MD², Jaison S. John, MD¹, Kevin Brown, MD¹, Fatima Iqbal, MBBS¹, Mohammad Abdallah, MD¹, Kashif Khan, MD¹. P0378 - A Pain in the Buttocks: An Unusual Presentation of Esophageal Adenocarcinoma, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.